Mercaptobenzothiazole/5 Use 2.2% of this in glycol antifreeze. It works well even if the glycol is diluted five times to give a 20% glycol solution. No.3 (New Improved Inhibitor Borax/70% Mercaptobenzothiazole/14% disodium Phosphate/16% Borax/95 Borax/90.9% Benzotriazole/9.1%